Air cleaner



Feb. 9, 1943- H. G. KAMRATH AIR CLEANER- Filed July 13, 1940 Ennentor$275575 6 YQIIIIMZZL Patented Feb. 9, 1943 2,310,528 r. AIR CLEANER.

Herbert G. Kamrath, Flint, Mich, assignor to General Motors Corporation,Detroit, Mich., a corporation of Delaware Application July 13, 1940,Serial No. 345,314

1 Claim.

This invention has to do with air cleaner and silencer assemblies andhas for its principal object to provide an assembly of a liquid-bathtype air cleaner and a side branch type silencer which is of cheap andsimple construction, re-

quires a minimum of space for its installation,

functions efiiciently and offers a minimum of resistance to the passageof air through it.

Other features of the invention are the construction and arrangement ofthe parts of the air cleaner and the construction and disposition of thesilencer with respect to the air cleaner and the orifice through whichair leaves the assembly.

For a better understanding of the nature and objects of this invention,reference is made to the accompanying specification wherein is describedthe preferred embodiment of the invention which is illustrated in theaccompanying drawing.

In the accompanying drawing:

Figure l is a vertical section through an air cleaner and silencerassembly in accordance with my invention.

Figure 2 is a section taken on the line 2--2 of Figure 1.

The air cleaner illustrated in the drawing includes a filter memberwhich consists of an annular container I filled with asuitable filtermedium II which is wetted with a suitable liquid before the air cleaneris put into use. The inner and outer walls of the filter member areimperforate but the lower and upper walls thereof have in them rings ofair inlet and outlet orifices l2 and I3. As the drawing shows, the innerwall of the filter member Ill-ll is in the form of a tube l4 whichextends to a point well above the upper edge of the outer wall.

To the filter member there is secured, by welding or in any othersuitable manner securing its outer edge to the lower wall of the filtermember without the orifices i2, a dished annular bafiie 5 with its inneredge almost directly below the inner edges of the orifices i2. Seatedagainst a gasket 16 disposed in an inverted channel formed in the outeredge of the baflie I5 is the upper edge of the side wall of a bowl-likemember ll whose bottom is' inclined upwardly from near its outer edge toits center. The bafile I5 is dished to such an extent that its inneredge is disposed well below the filter member but as to leave acomparatively narrow annular aperture I8 between it and the bottom ofthe bowl-like member l1. 7

Before the air cleaner is put into use the bowllike member I1 is filledto the level indicated in I the drawing with the liquid with which thefilter medium is wetted. This body of liquid is, as the drawing showsdivided by the baiiie [5 into two portions of which one is above and theother below the baflle. The portion of the body of liquid below thebaflie communicates with that above the baflle through the aperture l8but is not otherwise in communication with the atmosphere.

Over the upper end of the filter member there is disposed aninverted-cup-shaped cover IS with the lower edge of its side wall seatedon a gasket 20 disposed in a channel in the upper wall of the filtermember without the orifices l3. The interior of the cover [9 is dividedinto an air -inlet compartment 2| and an air outlet compartment 22 intowhich the air outlet orifices l3 in the filter member open by aninclined partition 23. From the compartment 22 in the zone of itsmaximum height there opens through the side wall of the cover an airoutlet orifice 24 and into the compartment 2| at a point diametricallyopposite the air outlet orifice 24 there opens an air inlet orifice 25.The center portion of the partition 23 is depressed at an angle to itsplane to provide a flange 26 which is seated on the upper end of thetube i4 through the intermediary of a gasket 21 and has in it an orifice28 which opens into the upper end of the tube.

To maintain the parts of the air cleaner in the relation in which theyhave been described there is provided a long thumbscrew 29 which Iextends through the cover l9 and is threaded into a member 30 suitablysecured in an orifice in the bottom of the bowl-like member l1.

In the air outlet orifice 24 in the cover l9 there is secured one end ofa fiattish tube 3| which has in its-lower side an air outlet orifice 32.The tube 3| is extended outwardly beyond the air outlet orifice 32 andclosed at its extremity to provide a sound wave attenuating recess 33.

The assembly shown in the drawing was designed for installation on aninternal combustion engine with the air outlet orifice 32 in the tube 3|connected to the air intake tube of the carburetor. When the assembly isso installed and the engine is operating the suction created by thepistons of the engine on their suction strokes draws air through the airinlet orifice 25 in the cover i 9 into the inlet compartment 2!, thence,through the tube l4 and the filter medium i I, into the Outletcompartment 22 in th cover i9, and thence;

through the orifice 24, the portion of the tube 3| between the orifice24 and the orifice 32 in the tube, and the orifice 32, into thecarburetor and cylinders of the engine. In the course of its passagethrough the assembly the air will, of course, be freed of foreign matterby the air cleaner.

The portion of the tube 3| between the orifice 32 and the closed end ofthe tube which constitutes the sound wave attenuating recess 33 ispreferably made equal in length to one-quarter of the wave length of themost objectionable sound wave in the intake noise of the engine on whichthe assembly is to be installed so that it will function as a closedtuning pipe to attenuate the most objectionable sound wave in the intakenoise of the engine and thus suppress the intake noise. In

the case of the engine for which the sound wave attenuating recessillustrated in the drawing was designed, which was the propelling engineof a well known make of automotive vehicle, the objectionable soundwaves of low frequency were sufficiently attenuated by a long air inletduct connected to the air inlet orifice of the air cleaner with whichthe sound wave attenuating recess was associated. To attenuate theremaining objectionable sound wave in the intake noise of this engine,the sound wave attenuating recess was made equal in depth to one-quarterof the wave length of this sound wave. This made the sound waveattenuating recess'about six (6) inches deep, and I apprehend that asound wave attenuating recess of about this depth will be efficacious insilencing the intake noises of the propelling engines of most, if notall, automotive vehicles because most, if not all, of them contain anobjectionable sound wave whose wave length is about four times adimension of this order.

In the course of its travel from the tube l4 into the filter medium IIof the air cleaner the air will, of course, strike the surface of theliquid in the bowl-like member I1 and pick up and carry some of it intothe filter medium. The battle I5 prevents the air from picking up theliquid below it and shields this portion of the pool of liquid in thebowl-like member from disturbance by the air. The bafile thus preventsthe air from picking up too much liquid when it is traveling at a rapidrate through the air cleaner and establishes below it a zone in whichthe foreign matterextracted from the air by the air cleaner can settleand from which it cannot again be picked up by the air traveling throughthe air cleaner.

The provision of the inclined partition 23 in the cover l9 reduces thetendency of the air to pass through the portion of the filter medium I lon the side of the air cleaner through which the air outlet orifice 24in the cover opens to the exclusion of the rest of the filter medium andthus promotes the etficiency of the air cleaner.

It is, of course, apparent that when the thumbscrew 29 is removed thebowl-like member [1, the filter member and bafile assembly |lll |l5 andthe cover l9 may be separated one from the others, which, of course,facilitates cleaning of the filter and bowl-like members and refillingthe bowl-like member with liquid when this becomes necessary.

I claim:

In an appliance of the class disclosed, a bowllike member whichconstitutes a liquid reservoir, an annular filter member with a centertube which extends upwardly beyond the level of the portion of thefilter member which encircles it disposed above the bowl-like memberwith the center tube and the portion of the filter member whichencircles it opening at their lower ends into the bowl-like member, acover shaped like an inverted bowl disposed above the filter member, aninclined partition which divides the interior of the cover into a lowercompartment into which the portion of the filter member which encirclesthe center tube opens at its upper end and an upper oompartment and hasin it a depression whose bottom is disposed at a right angle to the axisof and is seated on the upper end of the center tube of the filtermember with an orifice in it through which the upper compartment opensinto the tube, an air inlet orifice which opens into the uppercompartment through the side Wall of the cover, and an air outletorifice which opens from the lower compartment at its point of maximumheight through the side wall of the cover.

HERBERT G. KAMRATH.

